Not Applicable.
Not Applicable.
The present invention relates to a drive train for an amphibious vehicle and, more particularly, to a drive train where all of the drive shafts are continuously rotating and a propellor engaging mechanism exists aft of the transfer case for engaging and disengaging the propellor.
Amphibious vehicles present unique design challenges. Unlike cars and trucks, which are designed specifically to be driven on the land, and boats, which are designed specifically to be driven in water, amphibious vehicles must be designed to handle both tasks equally well. When driven on land, the body of an amphibious vehicle must drive like an ordinary road vehicle. On the other hand, when the amphibious vehicle is propelled in water, the vehicle must have the ability to maneuver like a boat. Therefore, the vehicle has to be provided with a propulsion system which drives both on land and in water.
In the past, a dual propulsion system was achieved by using a switching mechanism on the transfer case to allow the drive system to be used either for land or water. The switch allowed the propulsion system to drive the boat on land as well as in water, but had to be switched between the two. This type of arrangement needed a complex transfer case and switching mechanism to allow for transformation between the two. One such complex transfer case can be found in U.S. Pat. No. 5,562,066.
Another dual propulsion system was achieved by adding a small, two-speed transfer case between the primary transfer case and the transmission. This allowed the propellor to be driven off one shaft and the other shaft run to a second transfer case where it was then directed to the driving wheels. However, due to the short distance available between the rear of the transmission and the front of the main transfer case, it is difficult, if not impossible, to place any new or larger components in this limited space. The additional gearbox was located in this region of limited space and thus two very short drive shafts were provided. This configuration is very cramped and does not allow use of the very large truck-style automatic transmissions that are needed to transfer power of the large engines that are employed. More specifically, due to limited area between the transfer case and the automatic transmission, there is not enough room for the additional gear box and the large truck-style automatic transmissions and thus, the present invention arose.
Accordingly, it is an object of this invention to provide a simple amphibious propulsion system which operates both amphibious and ground drives wherein a simple transfer case can be utilized without any complex switch to select between land use or marine use.
Another object of this invention is to provide an amphibious propulsion system consisting of only one transfer case whose outputs continuously drive both the land and marine functions.
Another object of this invention is to provide a disengaging mechanism for the propellor located aft of the transfer case to allow the propellor shaft to be disengaged when not in use.
A still further object of this invention is to position the components of the drive train rearwardly to add further balance to the vehicle.
Accordingly, the present invention provides for a simple amphibious propulsion system including a drive train which is capable of propelling the vehicle on land and in water. The drive train comprises a motor rotatably coupled to a transmission via a drive shaft. The transmission is then rotatably coupled to a transfer case using another drive shaft. Each output drive shaft of the transfer case continuously run while the vehicle is in operation. Although the drive shafts are continuously rotating, an engaging mechanism for the propellor is located aft of the transfer case and before a gearbox to disengage the propellor when not in use.
Further objects, features, and advantages of the present invention over the prior art will become apparent from the detailed description of the drawings which follows, when considered with the attached figures.